Delicate articles are typically enclosed in a protective cushioning material when transported in a closed container such as a cardboard box. The protective material isolates the article from large forces and shocks which may occur due to rough handling of the shipping container. The protective material may take the form of crumpled newspaper, styrofoam beads, popcorn, and, in some cases, end caps positioned on opposed ends of the article such as an appliance or television receiver. The end caps are typically comprised of an expanded polystyrene and are sized to snugly fit in the closed container.
Trapped air is also used to isolate the article from rough handling. Early efforts in this area made use of a sheet-formed plastic material of two sheets of thin, pliable plastic, sealed together with a plurality of pockets of air or bubbles formed therein. This arrangement, commonly referred to as a "bubble pak", tends to transfer any load imposed on the bubble to the article and is also subject to bursting of a bubble as the bubble is deformed with a substantial increase in pressure. Other trapped air packaging inserts are inflatable and are better capable of absorbing shock. Examples of inflatable packaging inserts can be found in U.S. Pat. Nos. 3,346,101 to Pestka, 3,949,879 to Peterson et al., 4,551,379 to Kerr, 4,905,835 to Pivert et al., and 4,874,093 to Pharo.
These inflatable packaging inserts typically include a plurality of interconnected chambers and a valve arrangement permitting the inflation and deflation of the packaging insert. The packaging insert further typically includes a pair of spaced sheets attached in a sealed manner at selective locations to form the aforementioned inflatable chambers. Upon inflation, each individual chamber experiences greatest expansion along points generally midway between its end portions. This can be seen in the patent to Pivert (FIGS. 2a-3b), Kerr (FIGS. 2 and 15-17), and Peterson (FIGS. 1 and 2). Inflatable packaging inserts of this type leave the edges and corners of an article with less protection than the inner surface portions of the article. In addition, because the article is not firmly engaged along its edges and adjacent to its corners, the article is not securely and firmly maintained in position and is subject to displacement and jarring when the container is dropped on one of its edges or corners. Moreover, in order to firmly maintain the article in position along three orthogonal axes, prior art inflatable packaging inserts require completely enclosing the article and securely engaging the side portions of the outer surfaces of the article. Finally, these prior art approaches are undesirable environmentally in that they occupy large volumes such as in a landfill following disposal once no longer useable.
The present invention overcomes the aforementioned limitations of prior art inflatable packaging inserts by providing an inflatable, encapsulating package insert or liner which securely engages and supports the edges and corners of an article disposed within the insert and positioned within a closed package. The article engaging inner surface of the inflatable packaging insert not only provides increased protection, but also secure support for the article during shipping.